In 2018, US and Mexican authorities began tracking several chemists working for the Sinaloa Cartel in Mexico that were trying to synthesize fentanyl. The investigations included wiretaps in which criminal operators spoke openly of manufacturing fentanyl precursors to synthesize fentanyl, according to two counterdrug operators who worked on the case and spoke to InSight Crime on condition of anonymity.
The investigators estimated there were three “legitimate chemists” and “many more” clandestine chemists, or “cooks,” that were working on the project. Their goal was to train the cooks to work in what Mexican officials would later tell us were “confection” sites where fentanyl precursors, such as 4-anilino-N-phenethylpiperidine (ANPP), or fentanyl pre-precursors, such as 4-anilinopiperidine (4-AP), could be used to make fentanyl in a relatively easy manner.
The public got a glimpse of the case in December 2018 when authorities raided one clandestine facility in Mexico City and arrested four people. The Associated Press, quoting the Attorney General’s Office, said the lab was in a “middle-income neighborhood on Mexico City’s north side” and had its own “automated pill press.”
*This article is part of a two-year investigation that tracked the supply chain of precursor chemicals that aid in the production of methamphetamine and fentanyl in Mexico. Read the other articles of the investigation here and the full report here.
The case was remarkable in many respects, perhaps most notably because it was the only time we could find in our year-long investigation into precursors that the Mexican government has admitted openly that fentanyl was being synthesized in Mexico and not manufactured elsewhere.
Since then, it has become a Mexican government maxim to declare fentanyl is positively not being synthesized in Mexico in spite of significant evidence to the contrary. President Andrés Manuel López Obrador — or AMLO, as the Mexican president is popularly known — has repeatedly said, as he did during one of his recent daily conferences, that the synthetic opioid was “neither produced nor consumed” in the country.
On May 5, AMLO said authorities had seized a fentanyl shipment from Qingdao, China, at the Mexican Pacific port of Lázaro Cárdenas, which, for the president, was conclusive evidence that no fentanyl is being synthesized in Mexico.
“We have the proof!” he declared.
But while China, India, and other chemical industry hubs are most likely still producing fentanyl and fentanyl analogues — which are smuggled to places like Mexico, the United States, and Canada — the publicly available evidence shows Mexican criminal groups are probably producing a significant amount of fentanyl as well, albeit in a more rudimentary fashion.
Below, InSight Crime lays out these arguments and provides the evidence to support them.
Analyzing the Seizures
In its most recent threat assessment, the Drug Enforcement Administration (DEA) said that Mexican criminal organizations were “significantly involved in fentanyl production” and that criminal organizations like the Sinaloa Cartel and the Jalisco Cartel New Generation (Cartel de Jalisco Nueva Generación – CJNG) were “increasing the production of wholesale quantities of fentanyl in powder and pill forms.” And in a recent appearance in front of the US Congress, DEA Administrator Anne Milgram reiterated this stance.
“They are mass-producing fentanyl,” she said of the Sinaloa Cartel and the CJNG.
Recent reports on fentanyl have backed up this claim. The Commission on Combating Synthetic Opioid Trafficking, citing interviews with United States law enforcement, argued that fentanyl production in Mexico was increasing and that Chinese actors were now sending fentanyl precursors and less regulated substances to Mexico rather than the finished product. And a 2022 Brookings Institutereport— citing an “international drug policy expert” and current and former law enforcement, among others — said that Mexican criminal organizations were hiring chemists to develop precursors and produce fentanyl.
The consensus of US officials and US counternarcotics agents that Mexico-based criminal groups are accumulating fentanyl precursors and pre-precursors and synthesizing the vast majority of fentanyl in Mexico comes from two sources: seizure data and criminal investigations of the type cited above.
Since 2019, when China scheduled a series of fentanyl analogues and fentanyl precursors, seizures of fentanyl arriving by land, mostly along the US-Mexico border, have skyrocketed, while seizures arriving by air, much of which came from Asia, have dropped considerably. CBP’s seizures of substances containing fentanyl, for instance, amounted to about 6.6 tons in 2022. Of that, 6.4 tons were seized along the Southwest border, and 6.35 tons were detected at land-entry points. Meanwhile, seizures at international mail facilities have consistently declined.
Fentanyl seizures have also skyrocketed in Mexico over the last five years. In 2017, authorities reported seizing only 3,147 fentanyl pills; in 2021, that number climbed to 5.13 million pills, according to data provided by the Attorney General’s Office. By InSight Crime’s estimates — assuming each pill has 1.6mg of pure fentanyl — the 2017 seizures accounted for only 5 grams of pure fentanyl, while the 2021 seizures accounted for 8 kilograms of pure fentanyl.
However, there are problems with the data. Mexican authorities are notoriously opaque on drug trafficking statistics and seizures. InSight Crime requested data on precursor seizures at ports, and the navy, which runs the ports, shared very little information. Some of the seizures, like a 2020 seizure of N-phenethyl-4-piperidinone (NPP) and 4-anilino-N-phenethylpiperidine (ANPP) — two chemicals used for the synthesis of fentanyl — at the Ensenada port reported in the press, did not even appear on the database the navy provided. Other seizures were mysteriously revised by the López Obrador government, including reported seizures of drug labs, which went up precipitously when the army retroactively included hundreds of “inactive labs” in its numbers, Reuters reported.
What’s more, the United States and Mexico do not adjust for purity in their fentanyl seizure statistics. The purity of fentanyl coming from Mexico by land hovers below 10 percent, while the purity of fentanyl arriving via international mail or express consignment carrier such as FedEx is closer to 90 percent. As the Commission on Combating Synthetic Opioid Trafficking itself says, when purity is considered, the disparity between the two potential sources of finished fentanyl and fentanyl analogues — China versus Mexico — is considerably less. The difference in weight seized in the United States, for example, was three kilograms of fentanyl coming from Mexico for every two arriving from China — significant but hardly iron-clad proof of a huge disparity.
The Fentanyl Conundrum
Seizures, of course, are not an empirical indicator but rather an expression of tendencies, which could reflect a small portion of the story. This is especially true with fentanyl since dealers need only a trace amount to obtain their objectives, thus distorting the market in unprecedented ways. As noted by the Commission on Combating Synthetic Opioid Trafficking, the clearest illustration of these distortions is in the land-based seizures coming from Mexico. Drug trafficking organizations normally try to maximize purity when crossing frontiers into valuable consumer nations, thus maximizing their efficiency and profits. But fentanyl seizures at the US-Mexico border and throughout Mexico, on average, contain between 95% and 97% adulterants and additives, according to DEA and Mexican counternarcotics sources, suggesting these criminal groups do not see the need as it relates to fentanyl.
Fentanyl’s incongruity with the rest of the drug market may help explain the lack of transparency and consensus regarding the source of fentanyl production. The rise in fentanyl seizures in Mexico, for example, should be accompanied by a rise in the seizures of fentanyl laboratories in the country. However, in reply to our public information requests, Mexico’s Ministry of Defense (Secretaría de la Defensa Nacional – SEDENA), the National Guard, and the Attorney General’s Office (Fiscalía General de la República – FGR), which shared only general data on “synthetic drug laboratories,” said they had “zero” records of fentanyl lab seizures through the end of 2022. Former and active government officials from various security agencies in Mexico, as well as various criminal actors interviewed for this report, said that this information generally corresponded with their understanding of potential fentanyl production in Mexico as well.
What Mexico Gets Wrong About Its Fentanyl Problem
What appears in abundance are “laboratories” that press finished fentanyl into counterfeit pharmaceutical pills. An officer from Sinaloa’s State Police and a former federal law enforcement officer from Mexico told InSight Crime they had only found pill-pressing facilities and that all the laboratories they had seized were used to produce methamphetamine. This forms the core of the Mexican government’s position, reiterated by President López Obrador himself on various occasions, including in a morning press conference in March: that Mexico’s criminal organizations are taking finished fentanyl and transforming it into counterfeit pills.
“I maintain that more fentanyl arrives directly to the United States and Canada than here to Mexico,” he said. “What happens here is that they make pills, [then] they adulterate them.”
There is some logic behind this argument. As noted, fentanyl can be smuggled in trace amounts. It is also difficult to make from scratch. This means that industrial laboratories that are dedicated to producing other compounds but can be used to produce fentanyl on the side — such as the ones in China and India — have a decisive economic advantage over makeshift operations in the remote regions of Mexico. What’s more, the comparatively high costs of pre-precursors, such as NPP, which is used almost exclusively for making fentanyl, would make it extremely costly for Mexican criminal groups to source these necessary ingredients.
However, the debate has become fiercely political. For its part, Mexico blames the United States for allowing criminal groups easy access to US-purchased weapons and has long blamed its problems with violence on the United States’ voracious appetite for illegal drugs. There is also a tumultuous history between the United States and Mexico, especially as it relates to drug policy. The two countries have sparred about security issues for years, and the current rhetoric regarding the designation of Mexican criminal organizations as terrorist groups and the possible deployment of US military personnel to Mexico is clouding logic and smothering data.
Indeed, there is a third approach, something between making fentanyl from scratch and obtaining finished fentanyl from abroad. We will detail this process below, but authorities from both Mexico and the United States seem to agree that this method — which, in the simplest terms, takes a precursor and converts it into fentanyl — is something that is prevalent in Mexico.
For InSight Crime, it is not a question of if fentanyl is being synthesized in Mexico, it is a question of how much. Notwithstanding the Mexican government’s public position, there is an abundance of evidence suggesting that Mexico imports significant quantities of precursors and pre-precursors for the synthesis of fentanyl in Mexico, as well as evidence indicating Mexican criminal groups are synthesizing fentanyl in Mexico.
There is also history: Mexican criminal organizations went through a similar process with methamphetamine, experimenting with recipes and chemicals until they became self-reliant in terms of methamphetamine production and distribution. As we outline in the next section, that process appears to be underway as it relates to fentanyl.
Obtaining Fentanyl and Precursors in Mexico
While it is impossible to say how much fentanyl is produced in Mexico and how much is sourced abroad, criminal networks are obtaining both precursors and finished fentanyl the same way.
First, they use cargo ships or commercial aircraft. In May 2020, for example, Mexican Marines found close to 170 kilograms of NPP and ANPP disguised amongst a soap shipment from China at the Pacific port of Ensenada. More recently, in February 2023, Mexican authorities seized 304 kilograms of a “powder containing the piperidine molecule” at the Mexico City Airport — which can be used as a fentanyl pre-precursor in any synthesis route — and 3.3 tons of propionyl chloride in the port of Manzanillo, used as a pre-precursor in what is known as the Gupta method, which is one of the most prevalent methods of synthesizing the drug, but also in the agrochemical and pharmaceutical industries.
Second, criminals divert the chemicals from company production lines or siphon them from imports. In a recent high-profile case, Mexican authorities froze dozens of banking accounts of Grupo Pochteca, a chemical behemoth in Mexico. The investigation was led by Mexico’s Financial Intelligence Unit, the Marines, and the DEA, which found the company was importing the fentanyl pre-precursors NPP and 4-piperidone, and the precursor norfentanyl, before diverting them to criminal actors. Details of the report, which appeared in the Mexican newspaper Milenio, did not say how much or for how long these imports and subsequent diversions were taking place.
In a later report citing an intelligence document from the Mexican Government, Milenio mentioned that Grupo Pochteca and two other companies — Corporativo Escomexa and Corporativo y Enlace Ram — were diverting these substances to the Sinaloa Cartel and the CJNG. In November 2022, InSight Crime filed a freedom of information request about this case to Mexico’s Attorney General’s Office, but our requests were denied, given that the investigation was ongoing. We also requested comment from Grupo Pochteca about these allegations, to which they replied via email that the company and its subsidiaries have “never commercialized, sold, stored, or advertised” fentanyl precursors. They added that they adhere to all national and international regulations, and they reject any allegation linking them to illicit activities.
Third, the chemicals are arriving via neighboring countries. In 2017, for example, a former border patrol agent was captured driving ANPP from California to Mexico. In 2018, he pled guilty to conspiring to distribute the pre-precursor. For the prosecutor and counterdrug agent who worked the case, this was proof there was widespread production of fentanyl in Mexico by Mexican criminal organizations — the records showed the officer had received 13 other packages from the same post office in California arriving from China. Numerous experts and law enforcement also told us that other shipments of precursors may be going through Central America, most notably Guatemala, before being smuggled into Mexico. Guatemalan authorities recently seized several shipments of a substance containing fentanyl at the Atlantic port of Barrios, in Izabal, which allegedly came from eastern Europe.
The networks needed to import fentanyl and fentanyl precursors may also include government officials. In June 2022, during one of President López Obrador’s morning press conferences, the director of the Federal Commission Against Health Risks (Comisión Federal de Prevención de Riesgos Sanitarios – Cofepris), Alejandro Svarch Pérez, mentioned corruption inside the agency’s “basement,” his metaphor for the “dark areas” where nefarious activity happens. One type of corruption he highlighted revolved around petitions that companies filed to import scheduled drugs like fentanyl for medical use in Mexico. Svarch said these schemes were governed by the logic of “whomever pays, plays.”
Processing Fentanyl: ‘Confection’ Sites
Once in Mexico, the precursors or finished fentanyl are moved to clandestine laboratories for processing. There, if it is finished fentanyl, they are pressed into pills. If they are precursors, they undergo a rudimentary process of synthesizing fentanyl before being pressed into pills.
Fentanyl is very difficult to manufacture without some of the key precursors or pre-precursors. According to one government expert interviewed by InSight Crime, fentanyl production is also considerably more dangerous than the production of methamphetamine. It requires stricter laboratory discipline to avoid accidental overdoses, maintain some level of quality control, and even conduct some of the required chemical reactions, Dr. Silvia Cruz, a pharmaceutical chemist at the National Polytechnic Institute in Mexico City, told us.
But this may not be what Mexican cooks are doing. US sources told us that Mexican criminal organizations are taking 4-AP and using it to make ANPP, then fentanyl; or simply getting the ANPP and making fentanyl. Both methods are infinitely easier than making fentanyl from scratch without the precursors.
Mexican officials were not as specific. However, in response to a question about whether fentanyl was synthesized in Mexico, officials from Mexico’s Ministry of the Navy (Secretaría de Marina – SEMAR) mentioned they had identified a small number of facilities where fentanyl appeared to have been synthesized from ANPP.
And since 2019, the Mexican Army has registered two seizures of ANPP — both in the city of Culiacán — totaling 900 liters; and four seizures of NPP — two in Baja California, one in Puebla, and another one in Jalisco — totaling 172 liters, according to information provided to InSight Crime by SEDENA. The seizures were startling. According to the International Narcotics Control Board’s breakdown of fentanyl production, that amount of precursors could produce close to a ton of fentanyl, which, according to our calculations, would be enough to supply anywhere between a third and a fifth of the US market.
Mexican authorities generally referred to these as “confection” sites, i.e., places where some basic chemistry takes place, in addition to pill pressing and/or lacing legacy drugs with fentanyl. Confection is not a scientific term. It seems to be a means by which the Mexican government can thread the needle: It does not want to admit there are labs but is trying to acknowledge that something is occurring.
The façade is difficult to maintain. In part because of the seizures cited above and in part because there have also been at least two media reports from synthetic drug-production zones that appear to illustrate cooks manufacturing fentanyl, and one about a chemist from Mexico’s National Autonomous University who was arrested for presumably working in a clandestine fentanyl laboratory. A later Wall Street Journal report appeared to show at least a rudimentary version of a fentanyl laboratory with a brown jug that read, “Chinese chemical.” The cook said he was developing his own “formula.”
Becoming Independent Producers?
In 2008, Mexico established firmer controls over the import and use of ephedrine, pseudoephedrine, and phenylpropanolamine, which, until then, had been the main precursors to manufacture methamphetamine. Since then, traffickers have migrated to a 1-phenyl-2-propanone or P2P-based method, according to interviews with Mexico’s Attorney General’s Office. Although this precursor is not easy to handle and requires some expertise to synthesize and convert into high-quality methamphetamine, it has become the dominant method of production in Mexico.
To be sure, Mexican criminal networks are mass-producing some of the purest and most potent methamphetamine on the planet. P2P and what is known as methylamine fuel this market. And while both chemicals are available on the black market — and Mexican criminal networks are obtaining some of their precursors there — the consensus is that Mexican criminal networks now produce most of their own precursors using unscheduled or less regulated pre-precursors and essential chemicals.
Some of the evidence for this shift is in the seizure data. In recent years, Mexican authorities have seized almost all the P2P and methylamine in production zones and laboratories rather than at ports of entry, border entry points, or illegal entry points. While this pattern may be due to how Mexico has organized its regulatory bodies, security forces, and law enforcement agencies — as well as the corruption in and around the movement of goods through the ports of entry — it suggests that criminal networks are not importing P2P in large quantities. Instead, they seem to synthesize it from less-regulated chemicals or unscheduled pre-precursors in Mexico.
The same may be happening with regard to fentanyl. The 2018 investigation by Mexican and US officials in Mexico City cited at the onset of this story appeared to be a worrying indicator in this regard. After the announcement of the initial seizures, no more details were given out publicly, but one of the counterdrug operators told InSight Crime that one of those arrested was a chemistry professor from Mexico’s National Autonomous University (Universidad Nacional Autónoma de México – UNAM).
The counterdrug operator added that the raid included “two or three labs” where they were making fentanyl. The criminal groups were storing 300 kilograms of finished fentanyl they had synthesized in one of these spots, the source said, but Mexican authorities delayed the raid, and the fentanyl was gone by the time they seized the property.
The counterdrug operator added authorities also raided “two or three labs” where they were trying to make precursors from scratch using what are known as the Janssen and the Siegfried methods. If true, this would indicate that Mexican groups have long sought independence from outside chemical suppliers, as they have with methamphetamine. The account was publicly corroborated by a former DEA agent, Terry Cole, who told a US media outlet that dozens of chemists were trying to “change the fentanyl molecular analog to create a new synthetic version.”
“The goal is to utilize different chemical precursors; no longer relying on importing China’s chemicals,” Cole told the outlet.
The more recent seizures cited above indicate that this is still a work in progress. In fact, the rudimentary “confection” sites suggest that Mexican criminal networks continue to rely on precursors produced outside of Mexico. Some of this may be due to a lack of expertise or equipment. More likely, it has a simpler explanation: It may be cheaper and more effective to keep sourcing precursors, pre-precursors, and even fentanyl from abroad.
*Victoria Dittmar and Sara García contributed to this article.